Smelly Frogs Such As The Green Mountain Frog Offer Hope For Antimicrobial Future
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A green mountain frog (O. livida), displaying the pointed nose that tends to be a feature of this group of Asian frogs. Photo courtesy: Melanochromis.
Odorous frogs belonging to the genus Odorrhana are not popular with hobbyists for the very simple reason, as their name suggests, that they have a very strong odor associated with them. The smell of these amphibians is generally regarded as being highly unpleasant, having been likened to rotten fish as an example. There are 18 different species recognized through eastern parts of Asia, of which 13 are to be found in China, and they form part of the Ranidae family.
Nevertheless, these frogs could be crucial to our future survival, in spite of their foul odor, suggestive of decay. They are now known to be protected by more anti-bacterial substances than any other single group on the planet. There is real hope that these chemicals may serve as new weapons in the battle against antibiotic-resistant infections that are becoming a major problem worldwide.
Explanation of this protection
Chinese researchers Yun Zhang, Wen-Hui Lee and Xinwang Yang explain that scientists have long recognized frogs' skin as a rich potential source of new medicines of this type. Frogs live in warm, wet places where bacteria thrive and their skin has adapted to secrete specific chemicals, known as peptides, to protect themselves from infections. Zhang's group wanted to identify these specific antimicrobial peptides (AMPs), and pick out the most potent, in order to assist further research into the development of new antibiotics.
The scientists have already identified more than 700 of these substances from just nine species of odorous frogs and conclude that their AMPs account for almost one-third of all AMPs found in the world. This represents the greatest known diversity of germ-killing chemicals of this type amongst related species on the planet.
Importance of biodiversity
The team's research therefore reinforces just how important maintaining biodiversity and protecting species may turn out to be, in order to assist our battle against disease in the future. Even more interestingly, some of the AMPs that have been identified have been shown to have a dual action. Not only are they effective at killing bacteria directly, but they are also capable of activating the body's immune system to assist in the battle against infection as well.
Reference: Xinwang Yang, Wen-Hui Lee, Yun Zhang. Extremely Abundant Antimicrobial Peptides Existed in the Skins of Nine Kinds of Chinese Odorous Frogs. Journal of Proteome Research, 2011; : 111118134814004 DOI: 10.1021/pr200782u